Note: Descriptions are shown in the official language in which they were submitted.
~6558/VB CA 02231294 1998-03-06
ORAL COMPOSITIONS FORMING A COACERVATE GEL
BACKGROUND OF THE INVENTION
The present invention relates to dentifrice formulations which contain a
coacervate gel. The coacervate gel is formed by combining an anionic,
cationic, and/or
amphoteric surfactant with a charged polymer. The coacervate gel is then
combined with
the additional carrier materials to form the dentifrice composition. The
dentifrice
formulation may contain two separate dentifrice compositions or a single
dentifrice
composition.
Coacervate gels are known in the art. Coacervate gels are commonly formed in
shampoos and other soaps. Coacervate gels are used to deposit active
substances on a
target surface. Examples include U.S. Patent 5,476,660, to Somasundaran et
al., issued
December 19, 1995. Coacervate gels are also used to form microcapsules.
Typically, the
microcapsule will comprise perfumes, silica, or other substances to be
deposited. An
example of a microcapsule formed by a coacervate gel includes U.S. Patent
5,126,061,
issued June 30, 1992, to Michael. In the present invention, a coacervate gel
is formed
but it is not used to microencapsulate a substance.
Also known in the art are the polymers used to form the coacervate gels.
Although these polymers are used in dentifrices, the polymer used are
neutralized and do
not remain charged. For example. U.S. Patent 4,988,500 to Hunter et al.,
issued January
29, 1991. describes the use of a carboxyvinyl polymer in a dentifrice. In the
present
invention, the polymer will remain charged to form a coacervate gel with the
surfactant.
It is knowm that dentifrice aesthetics can be improved by optimizing the
foaming
and product consistency. The present inventor has discovered that a dentifrice
with
improved sensory attributes can be made by forming a coacervate gel. By
forming a
coacervate gel in the dentifrice composition, the dentifrice and foam have a
creamier
consistency and a slick, smooth teeth feeling is achieved. Additionally, the
dentifrice
may also provide a longer lasting flavor. Therefore, it is an object of the
present
invention to provide stable dentifrice formulations comprising a coacervate
gel. The
dentifrice formulation may be a single composition with a coacervate gel or a
dual phase
composition in which one or both dentifrice compositions comprise a coacervate
gel. It
is also an object of the present invention to provide a method of making a
dentifrice
formulation with a coacervate gel.
These and other objects of the present invention will become readily apparent
from the detailed description which follows.
CA 02231294 1998-03-06
2
All percentages and ratios used herein are by weight of the specific
dentifrice
composition and not of the overall dentifrice formulation that is delivered,
unless
otherwise specified. All measurements are made at 25° C, unless
otherwise specified.
SUMMARY OF THE INVENTION
The present invention relates to a dentifrice formulation comprising first and
second dentifrice compositions and to a dentifrice formulation that is a
single dentifrice
composition. The first dentifrice composition or the single dentifrice
composition will
comprise from about 0.1 % to about 10% of a surfactant selected from the group
consisting of anionic surfactants, cationic surfactants, amphoteric
surfactants, and
mixtures thereof; from about 0.1 % to about 10% of a charged polymer; and from
about
80% to about 99% of pne or more aqueous carriers; wherein the charged polymer
is
diluted to form a charged polymer slurry and the pH of the charged polymer
slurry is
from about 1.5 to about 10, the charged polymer slurry is combined with the
anionic,
cationic, or amphoteric surfactant to form a coacervate gel, and the
coacervate gel is then
combined with the one or more aqueous Garners to form the dentifrice
composition. The
present invention also relates to a method of making a dentifrice composition
containing
a coacervate gel, comprising the steps of diluting from about 0.1 % to about
10% of a
charged polymer to form a charged polymer slurry, the charged polymer slurry
having a
pH of from about 1.5 to about 10; combining the charged polymer slurry with
from about
0.1 % to about I 0% of a surfactant selected from the group consisting of
anionic
surfactants, cationic surfactants, amphoteric surfactants, and mixtures
thereof, to form a
coacervate gel; and combining the coacervate gel with from about 80% to about
99% of
one or more aqueous carriers to form the dentifrice composition.
DETAILED DESCRIPTION OF THE INVENTION
The dentifrice formulation of the present invention may be in the fonm of a
toothpaste or dentifrice. The term "dentifrice formulation" as used herein
means the total
dentifrice that is delivered to the oral surfaces. The dentifrice formulation
may be a
combination of the two or more dentifrice compositions or may be a single
dentifrice
composition. The dentifrice formulation is a product, which in the ordinary
course of
usage, is not intentionally swallowed for purposes of systemic administration
of
particular therapeutic agents, but is rather retained in the oral cavity for a
time sufficient
to contact substantially all of the dental surfaces and/or oral tissues for
purposes of oral
activity.
The term "dentifrice", as used herein, means paste, gel, or liquid
formulations
unless otherwise specified. The dentifrice composition may be in any desired
form, such
as deep striped, surface striped. multilayered, having the gel surrounding the
paste, or
CA 02231294 2001-02-19
any combination thereof. The dentifrice composition may be contained in a
physically
separated compartment of a dispenser and dispensed side-by-side or may be a
single
composition.
The term "dispenser", as used herein, means any pump, tube, or container
suitable
for dispensing dentifrice.
The term "aqueous carrier" as used herein means any safe and effective
materials
for use in the compositions of the present invention. Such materials include
alkali metal
bicarbonate salts, calcium peroxide, abrasive polishing materials, propylene
glycol,
acidic compounds, buffering agents, polyoxyethylene, thickening materials,
humectants,
water, surfactants, titanium dioxide, flavor system, coolants, sweetening
agents, xylitol,
coloring agents, antimicrobial agents, and mixtures thereof.
The present compositions comprise essential components, as well as optional
components. The essential and optional components of the compositions of the
present
invention are described in the following paragraphs.
Surfactants
Anionic, cationic, andJor amphoteric surfactants are required in the present
invention. Suitable surfactants. commonly referred to as sudsing agents, are
those which
are reasonably stable and foam through a wide pH range. Anionic surfactants
useful
herein include the water-soluble salts of alkyl sulfates having from 8 to 20
carbon atoms
in the alkyl radical (e.g., sodium alkyl sulfate) and the water-soluble salts
of sulfonated
monoglycerides of fatty acids having from 8 to 20 carbon atoms. Sodium lauryl
sulfate
and sodium coconut monoglyceride sulfonates are examples of anionic
surfactants of this
type. Other suitable anionic surfactants are sarcosinates, such as sodium
lauroyl
sarcosinate, taurates, sodium lauryl sulfoacetate. sodium lauroyl isethionate.
sodium
laureth carboxylate, and sodium dodecyl benzenesulfonate.
Preferred cationic suc-factants useful in the present invention can be broadly
defined as derivatives of aliphatic quaternary ammonium compounds having one
long
alkyl chain containing from about 8 to 18 carbon atoms. Suitable cationic
surfactants
include ethoxylated fatty amines. fatty ammonium chlorides, fatty pyridinium
chlorides,
fatty dimethylamines, fatty dimethylamine lactates, and mixture thereof.
Specific
cationic surfactants include lauryl trimethylammonium chloride, cetyl
pyridinium
chloride, cetyl trimethylammonium bromide. di-isobutylphenoxyethyl-
dimethylbenzylammonium chloride, coconut alkyltrimethylammonium nitrite, and
cetyl
pyridinium fluoride. The quaternary ammonium fluorides are described in
U.S. Patent No. 3,535,421, October 20, 1970, to Briner et al. Certain
CA 02231294 2001-02-19
4
cationic surfactants, such as chlorhexidine, can also act as antimicrobials in
the
compositions.
The amphoteric surfactants useful in the present invention can be broadly
described as derivatives of aliphatic secondary and tertiary amines in which
the aliphatic
radical can be a straight chain or branched and wherein one of the aliphatic
substituents
contains from about 8 to about 18 carbon atoms and one contains an anionic
water-
solubilizing group, e.g., carboxylate, sulfonate, sulfate, phosphate, or
phosphonate.
Other suitable amphoteric surfactants are betaines, specifically
cocamidopropyl betaine.
Mixtures of amphoteric surfactants can also be employed, as well as mixtures
of anionic,
cationic, and/or amphoteric surfactants.
Many surfactants suitable for use are disclosed by Gieske et al., U.S. Patent
4,051,234, issued September 27, 1977. The present composition
typically comprises one or more surfactants at a level of from
about 0.1% to about 10%, preferably from about 0.2% to about 8%, and most
preferably
from about 0.25% to about 6%, by weight of the composition.
Charged Polymer
The present invention also comprises a charged polymer. The charged polymer
will be anionic or cationic. Preferably, the charge of the polymer should be
opposite the
charge of the surfactant if an amphoteric surfactant is not present by itself
or in
combination with another surfactant. For example, if the charged polymer is
anionic, the
surfactants may be amphoteric; cationic; amphoteric and cationic; amphoteric
and
anionic; or amphoteric, anionic. and cationic. Suitable cationic polymers
include
canonically modified guar gum. polyquaternary amines, and polyacrylamides.
Suitable
anionic polymers include polyacrylic acids, polyvinyl acetates, polymaleic
acid,
polycarbonates, polysulfonates. and mixtures thereof. Additional anionic
polymeric
polycarboxylates, such as Gantrez. are described in U.S. Patent 5.0376,37 to
Gaffar et al,
issued August 6, 1991. The preferred anionic polymer is a carboxyvinyl
polymer. Carboxyvinyl polymers are described in U.S. Patent No. 2,798,053
to Brown, issued July 2, 1957. Carboxyvinyl polymers are provided by
B.F. Goodrich Company as CarbopolTM 934, 940, 941, 946, and 956.
ane provided by B.F. Goodrich Company as Carbopol 934, 940, 941, 946, and 9~6.
Mixtures of charged polymers can also be employed. The present composition
typically
comprises a charged polymer at a level of from about 0.1 % to about 10%,
preferably
from about 0.2% to about 8°/~, and most preferably from about 0.2~% to
about 6%, by
weight of the dentifrice composition.
Coacen~ate Gel
CA 02231294 2001-02-19
Coacervate formation is dependent upon a variety of criteria such as molecular
weight, component concentration, and ratio of interacting ionic components,
ionic
strength (including modification of ionic strength, for example, by addition
of salts),
charge density of the cationic and anionic components, pH, and temperature.
Coacervate
systems and the effect of these parameters have been described, for example,
by J.
Caelles, et al., "Anionic and Cationic Compounds in Mixed Systems", Cosmetics
&
Toiletries, Vol. 106, April 1991, pp 49-54, C. J. van Oss, "Coacervation,
Complex-
Coacervation and Flocculation", J. Dispersion Science and Technology, Val. 9
(~,6).
1988-89, pp 561-573, and D. J. Burgess, "Practical Analysis of Complex
Coacervate
Systems", J. of Colloid and Interface Science, Vol. 140, No. 1, November 1990,
pp 227-
238.
The coacervate gel of the present invention comprises anionic, cationic,
and/or
amphoteric surfactants and a charged polymer. The coacervate gel is formed by
combining the charger polymer with the surfactant. Preferably, the charged
polymer is
contained in a slurry. The charged polymer slurry will have a pH of from about
1.5 to
about 10. An anionic polymer slurry will have a pH of from about 1.5 to about
7 and
preferably from about 1.5 to about 4.5. A cationic polymer slurry will have a
pH of from
about 7 to about 10 and preferably from about 7.5 to about 9. The slurry may
comprise
humectants and/or water. Preferred humectants include glycerin and sorbitol.
The ratio
of charged polymer to humectant is from about 1:20 to about 1:100, preferably
from
about 1:30 to about i :60. The charged polymer slurry is then combined with
the
surfactant. This forms the coacervate gel. A coacervate gel formed by an
anionic
polymer will have a pH of from about 3 to about 7, preferably from about 4.5
to about
6.~. and more preferably from about 4.5 to about 6Ø A coacervate gel formed
by a
cationic surfactant will have a pH of from about 7 to about 9 and preferably
from about 8
to about 8.5. After the coacervate gel is formed, it may be neutralized with a
buffering
agent to form the dentifrice composition. The final pH of the dentifrice
composition will
be from about 4 to about 8.5. The final pH of a dentifrice composition
containing a
coacervate gel made with an anionic polymer will be from about 5 to about 6.
The coacervate gel rnay additionally comprise a flavor system or other
hydrophobic species. If a hydrophobic species is present, it will be
emulsified with the
surfactant. The emulsified surfactant and hydrophobic species will then be
added to the
charged polymer slurry to four}, the coacervate gel.
Fluoride Ion Source
The first and/or secand dentifrice compositions or the single dentifrice
composition of the present invention may incorporate a soluble fluoride ion
source
CA 02231294 2001-02-19
6
capable of providing free fluoride ions. Preferred soluble fluoride ion
sources include
sodium fluoride, stannous fluoride. indium fluoride, and sodium
monofluorophosphate.
Sodium fluoride is the most preferred soluble fluoride ion source. Norris et
al., U.S.
Patent 2,946,725, issued July 26, 1960, and Widder et al., U.S. Patent
3,678,154 issued
July 18, 1972, disclose such fluoride ion sources as well as
others. The fluoride ion source should be capable of providing
from about 50 ppm to about 3500 ppm, and preferably from about
500 ppm to about 3000 ppm of free fluoride ions.
Tartar Control Agents
The present invention may include a tartar control agent. The tartar control
agent
may be present in the first or second dentifrice compositions, both
compositions, or in
the single dentifrice composition. The tartar control agent may be any
materials known
to be effective in reducing calcium phosphate mineral deposition related to
calculus
formation. The preferred tartar control agent is selected from the group
consisting of a
polyphosphate source. tripolyphosphate source, a pyrophosphate salt. and
mixtures
thereof.
The pyrophosphate salts useful in the present compositions include the di and
tetra alkali metal pyrophosphate salts. and mixtures thereof. Disodium
dihydrogen
pyrophosphate (Na~H~P~Cy7). tetrasodium pyrophosphate (Na4P207), and
tetrapotassium pyrophosphate (K4P~07) in their unhydrated as well as hydrated
forms
are the preferred species. In compositions of the present invention. the
pyrophosphate
salt may be present in one of three ways: predominately dissolved,
predominately
undissolved, or a mixture of dissolved and undissolved pyrophosphate.
Compositions comprising predominately dissolved pyrophosphate refer to
compositions where at least one pyTOphosphate ion source is in an amount
sufficient to
provide at least about 1.0°~o free pyTOphosphate ions. Compositions
comprising
pyrophosphate typically containing from about 1 % to about 15%, preferably
from about
2% to about 10%, and most preferably from about 2% to about 8%, by weight of
the
composition. The pyrophosphate salts are described in U.S. Patent 4,515,772,
issued
May 7, 1985. and 4.88.155. issued December ~, 1989, both to Parran et al.
The present invention may include a polyphosphate source. A polyphosphate is
generally understood to consist of two or more phosphate molecules arranged
primarily
in a linear configuration. although some cyclic derivatives may be present.
The
inorganic pol~~phosphate salts desired include sodium tripolyphosphate,
CA 02231294 2001-02-19
7
tetrapolyphosphate, and hexametaphosphate, among others. Polyphosphates larger
than
tetrapolyphosphate usually occur as amorphous glassy materials. Preferred are
polyphosphates manufactured by FMC Corporation which are commercially known as
Sodaphos (n~6), Hexaphos (:n~13), and Glass H (n=21). The polyphosphate source
will
typically comprise from about 0.5% to about 20%, preferably from about 4% to
about
I 5%, more preferably from about 6% to about 10%, and most preferably from
about 7%
to about 9%, by weight of the dentifrice composition.
The phosphate sources are described in more detail in Kirk & Othmer,
Encyclopedia of Chemical Technology, Fourth Edition, Volume 18, Wiley-
Interscience
Publishers (1996), pages 685-707. Optional agents to be used
in place of or in combination with the polyphosphate or
pyrophosphate salt include such materials known to be
effective in reducing calcium phosphate mineral deposition related
to calculus formation. Agents included are synthetic anionic polymers
[including
polyacrylates and copolymers of malefic anhydride or acid and methyl vinyl
ether (e.g.,
Gantrez), as described, for example, in U.S. Patent No. 4,627,977,
to Gaffar et al., as well as, e.g., polyamino propane sulfonic
acid (AMPS)], zinc citrate trihydrate, diphosphonates (e.g.,
EHDP; AHP), polypeptides (such as polyaspartic and polyglutamic acids), and
mixtures
thereof.
Aqueous Carriers
In preparing the present compositions, it is desirable to add one or more
aqueous
carriers to the dentifrice compositions. Such materials are well known in the
art and are
readily chosen by one skilled in the art based on the physical and aesthetic
properties
desired for the compositions being prepared. Aqueous carriers typically
comprise from
about 10% to about 99%, preferably from about 45% to about 98%, and more
preferably
from about 75% to about 95°~0, by weight of the dentifrice composition.
Alkali Metal Bicarbonate Salt
The dentifrice compositions of the present invention may also include an
alkali
metal bicarbonate salt. The alkali metal bicarbonate salt may be present in
one or both
dentifrice composition or in the single dentifrice composition. Sodium
bicarbonate, also
known as baking soda. is the preferred alkali metal bicarbonate salt. The
present
composition may contain from about 6% to about 50%, preferably from about 7%
to
about 30%, more preferably from about 8% to about 20%, and most preferably
from
about 8% to about 18% of an alkali metal bicarbonate salt, by weight of the
dentifrice
composition.
CA 02231294 2001-02-19
8
Calcium Peroxide
The present invention may include calcium peroxide in any of the dentifrice
compositions. The following amounts represent the amount of peroxide raw
material.
although the peroxide source may contain ingredients other than the peroxide
raw
material. The present composition may contain from about 0.01% to about 10%,
preferably from about 0.1 % to about 5%, more preferably from about 0.2% to
about 3%,
and most preferably from about 0.3% to about 0.8% of a peroxide source, by
weight of
the dentifrice composition.
Abrasive Polishing Materials
An abrasive polishing material may also be included in the dentifrice
compositions. The abrasive polishing material contemplated for use in the
compositions
of the present invention can be any material which does not excessively abrade
dentin.
Typical abrasive polishing materials include silicas including gels and
precipitates;
aluminas; phosphates including orthophosphates, polymetaphosphates, and
insoluble
pyrophosphates; and mixtures thereof. Silica dental abrasives of various types
are
preferred because of their unique benefits of exceptional dental cleaning and
polishing
performance without unduly abrading tooth enamel or dentine. The silica
abrasive
polishing materials herein, as well as other abrasives, generally have an
average particle
size ranging between about 0.1 to about 30 microns, and preferably from about
5 to about
1 ~ microns. The abrasive can be precipitated silica or silica gels such as
the silica
xerogels described in Pader et al.. U.S. Patent 3,538.230. issued Mar. 2,
1970, and
DiGiulio, U.S. Patent No. 3,862,307, issued January 21, 1975. Preferred
are the Precipitated silica materials such as those marketed by the J.
M. Huber Corporation under the trade mark, "Zeodent", particularly the silica
carrying
the designation "Zeodent 119". The types of silica dental abrasives useful in
the
toothpastes of the present invention are described in more detail in Wason,
U.S. Patent
4.340.583, issued July 29, 1982. and in Rice, U.S. Patent 5,589,160, issued
December
31, 1996. Silica abrasives described in U.S. Patent Nos. 5,651,958
and 5,658,553 issued July 29, 1997 and August 19, 1997,
respectively. The abrasive in the toothpaste compositions described herein
is generally present at a level of from about 6% to about 70% by weight of the
composition. Preferably, toothpastes contain from about 10% to about 50% of
abrasive,
by weight of the dentifrice composition.
Propylene Glycol
The dentifrice compositions may also comprise propylene glycol. The propylene
glycol is suitable for use on the skin and mucosal surfaces such as in the
oral cavity. The
CA 02231294 1998-03-06
9
first dentifrice composition may contain from about 0.5% to about 30%,
preferably from
about 1 % to about 20%, and more preferably from about 2% to about 15% of
propylene
glycol, by weight of the dentifrice composition.
Acidic Compound
The dentifrice compositions of the present invention may incorporate an acidic
compound. The acidic compound may be organic or inorganic. The acidic compound
may be any material which will be a proton donor that is capable of
neutralizing
bicarbonate. Acidic compounds suitable for use include carboxylic acids,
phosphoric
acids, alpha-hydroxy acids, sulfonic acids, and mixture thereof. Specific
acids include
citric acid, malic acid, alginic acid, succinic acid, lactic acid, tartaric
acid, glycolic acid,
adipic acid, potassium bitartrate acid, acid sodium citrate, phosphoric acid,
boric acid,
and acid phosphate and pyrophosphate salts. A blend of acids are preferred.
Citric acid
and malic acid are preferred. Acid anhydrides and acid salts of the above
acids may also
be used. Suitable salts include mono or disodium salts of citric acid, mono
sodium salts
of malic acid, and mixtures thereof. The second dentifrice composition may
contain
from about 0.5% to about 20%, preferably from about 1% to about 15%, and more
preferably from about 4% to about 12% of an acidic compound. by weight of the
dentifrice composition.
Buffering-Agent
The dentifrice compositions may contain a buffering agent. Buffering agents,
as
used herein, refer to agents that can be used to adjust the pH of the
compositions. The
buffering agents suitable include alkali metal hydroxides, carbonates,
sesquicarbonates,
borates. silicates, phosphates, imidazole, and mixtures thereof. Specific
buffering agents
include monosodium phosphate. trisodium phosphate, sodium hydroxide, potassium
hydroxide, alkali metal carbonate salts, sodium carbonate, imidazole,
pyrophosphate
salts, sodium acid pyrophosphate, sodium citrate, and sodium malate. Buffering
agents
are used at a level of from about 0.1 % to about 30%, preferably from about 1
% to about
10%, and more preferably from about 1.5% to about 3%, by weight of the
dentifrice
composition.
Polvoxyeth~rlene
The present invention may include a polyoxyethylene. The polyoxyethylene will
increase the amount of foam and the thickness of the foam. Polyoxyethylene is
also
commonly known as polyethylene glycol ("PEG") or polyethylene oxide. The
polyoxyethylenes suitable for this invention will have a molecular weight of
from about
200,000 to about 7,000,000. Preferably, the molecular weights will be from
about
600,000 to about 2,000.000. and more preferably from about 800,000 to about
1,000,000.
CA 02231294 2001-02-19
l0
"Polyox" is the trademark for the high molecular weight polyoxyethylene
produced by
Union Carbide. The polyoxyethylene is present in an amount of from about 0.1%
to
about 8%, preferably from about 0.2% to about 5%, and more preferably from
about
0.3% to about 2%, by weight of the dentifrice composition.
Additional Aqueous Carriers
The present invention compositions in the form of toothpastes, typically
contain
some thickening material or binders to provide a desirable consistency.
Preferred
thickening agents are carboxyvinyl polymers, carrageenan, hydroxyethyl
cellulose, and
water soluble salts of cellulose ethers such as sodium carboxymethylcellulose
and
sodium hydroxyethyl cellulose. Natural gums such as gum karaya, xanthan gum,
gum
arabic, and gum tragacanth can also be used. Colloidal magnesium aluminum
silicate or
finely divided silica can be used as part of the thickening agent to further
improve
texture. Thickening agents can be used in an of amount from about 0.1 % to
about 15%,
by weight of the dentifrice composition.
Another optional component of the compositions desired herein is a humectant.
The humectant serves to keep toothpaste compositions from hardening upon
exposure to
air and certain humectants can also impart desirable sweetness of flavor to
toothpaste
compositions. Suitable humectants for use in the invention include glycerin,
sorbitol,
polyethylene glycol, and other edible polyhydric alcohols. The polyethylene
glycol may
have a molecular weight of from about 200 to about 7000. The humectant
generally
comprises from about 0% to TO%, and preferably from about 15% to 55%, by
weight of
the dentifrice composition.
Water employed in the preparation of commercially suitable dentifrice
compositions should preferably be of low ion content and free of organic
impurities.
Water will generally comprise from about 5% to about 70%, and preferably from
about
10% to about 50%, by weight of the composition herein. Alternatively, the
dentifrice
compositions may comprise a lower level of water, generally from about 5% to
about
20%, preferably from about 7% to about 14%, and more preferably from about 7%
to
about 12%, by weight of the dentifrice composition. The lower level of water
is
preferred in compositions comprising polyphosphates. The amounts of water
include the
free water which is added plus that which is introduced with other materials,
such as with
sorbitol, silica, surfactant solutions, and/or color solutions.
The present compositions may also comprise additional surfactants, also
commonly referred to as sudsing agents. The additional surfactant may be
nonionic.
Nonionic surfactants which can be used in the compositions of the present
invention can
be broadly defined as compounds produced by the condensation of alkylene oxide
groups
CA 02231294 2001-02-19
(hydrophilic in nature) with an organic hydrophobic compound which may be
aliphatic
or alkyl-aromatic in nature. Examples of suitable nonionic surfactants include
poloxamers (sold under trade mark Pluronic), polyoxyethylene, polyoxyethylene
sorbitan esters (sold under trade mark Tweens), and mixtures of such
materials. Many
suitable nonionic surfactants are disclosed by Gieske et al., U.S. Patent
4,051,234, issued
September 27, 1977. The present composition may comprise one
or more surfactants each at a level of from about 0.25%
to about 12%, preferably from about 0.5% to about 8%, and most preferably from
about
I % to about 6%, by weight of the composition.
Titanium dioxide may also be added to the present composition. Titanium
dioxide is a white powder which adds opacity to the compositions. Titanium
dioxide
generally comprises from about 0.2~% to about 5%, by weight of the
composition.
Coloring agents may also be added to the present composition. The coloring
agent may be in the form of an aqueous solution, preferably 1 % coloring agent
in a
solution of water. Color solutions generally comprise from about 0.01% to
about 5%, by
weight of the composition.
A flavor system can also be added to the compositions. Suitable flavoring
components include oil of wintergreen, oil of peppermint, oil of spearmint,
clove bud oil,
menthol, anethole, methyl salicylate, eucalyptol, cassia, I-menthyl acetate,
sage, eugenol,
parsley oil, oxanone. alpha-irisone, marjoram, lemon, orange, propenyl
guaethol,
cinnamon, vanillin. ethyl vanillin, heliotropine, 4-cis-heptenal, diacetyl,
methyl-para-tert-
butyl phenyl acetate, and mixtures thereof. A flavor system is generally used
in the
compositions at levels of from about 0.001 % to about 5%, by weight of the
composition.
Coolants may also be pan of the flavor system or added separately to the
composition. Preferred coolants in the present compositions are the
paramenthan
carboxyamide agents such as N-ethyl-p-menthan-3-carboxamide (known
commercially
as "WS-3") M menthol, 3-1-menthoxypropane-1,2-diol ("TK-10")M menthone
glycerol
acetal ("MGA"), menthyl lactate, and mixtures thereof. A coolant is generally
used in
the compositions at levels of from about 0.001 % to about 5%, by weight of the
composition.
The present invention rnay also include xylitol. Xylitol is a sugar alcohol
that is
used as a sweetener and humectant. Xylitol may provide a therapeutic effect,
such as an
antibacterial or anticaries effect. The present compositions typically
comprise xylitol at a
level from about 0.01 % to about 25%, preferably from about 3% to about 1 S%,
more
preferably from about 5% to about 12%, and most preferably from about 9% to
about
11 %, by weight of the total composition. Alternatively, if xylitol is used as
a sweetener,
CA 02231294 2001-02-19
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it may be present at a lower Level, such as from about 0.00% to about 5%, by
weight of
the dentifrice composition.
Sweetening agents can be added to the compositions. These include saccharin.
dextrose, sucrose, lactose, maltose, levulose, aspartame, sodium cyclamate. D-
tryptophan, dihydrochalcones, acesulfame, and mixtures thereof. Various
coloring
agents may also be incorporated in the present invention. Sweetening agents
and
coloring agents are generally used in toothpastes at levels of from about
0.005% to about
5%, by weight of the composition.
The present invention may also include other agents, such as antimicrobial
agents. Included among such agents are water insoluble non-cationic
antimicrobial
agents and water soluble antimicrobials, such as quaternary ammonium salts and
bis-
biquanide salts, among others. Triclosan monophosphate is an additional water
soluble
antimicrobial agent. Other compounds are bis[4-(R-amino)-1-pyridinium] alkanes
as
disclosed in U.S. Patent No. 4,206,215, issued June 3, 1980, to Bailey.
Stannous salts such as stannous pyrophosphate and stannous gluconate and
other antimicrobials such as copper bisglycinate, copper glycinate, zinc
citrate, and zinc
lactate may also be included. Also useful are enzymes, including
endaglycosidase,
papain, dextranase, mutanase, and mixtures thereof. Such agents are disclosed
in U.S.
Patent 2,946.72, Jul. 26, 1960. to Norris et al. and in U.S. Patent 4,0~ I
,234, September
27, 1977 to Geiske et al. Specific antimicrobial agents include
chlorhexidine, triclosan, t:riclosan monophosphate, and flavor oils such as
thymol. Triclosan and other agents of this type are disclosed in Parran, Jr.
et al., U.S.
Patent x.015,466. issued May 14. 1991. and U.S. Patent 4,894,220, Jan. 16,
1990 to Nabi
et al. These agents may be present at levels of from about
0.01% to about I.5%, by weight of the dentifrice composition.
The dentifrice formulation may contain a first and second dentifrice
composition
or a single dentifrice composition. If there are two dentifrice compositions,
the first and
second dentifrice compositions will be physically separated in a dentifrice
dispenser.
The dentifrice compositions may be a paste, gel, or any configuration or
combination
thereof. It is preferred that the first dentifrice composition be a gel and
the second
dentifrice composition be a paste. The dispenser may be a tube, pump, or any
other
container suitable for dispensing toothpaste. Dual compartment packages
suitable for
this purpose are described in U.S. Patent 4,528,180, issued July 9, 1985; U.S.
Patent
4.687.663. issued August 18., 1987; and 4,849,213, issued July 18, 1989, all
to Shaeffer.
The dispenser will deliver approximately equal amounts of each
dentifrice composition through an opening. The compositions may
CA 02231294 2001-02-19
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intermix once dispensed. Alternatively, the dentifrice formulation may be
delivered from
a kit containing two separate dispensers which are used to deliver two
dentifrice
compositions that are both used simultaneously.
Method of Treatment
The method of treatrrrent herein comprises contacting the dental enamel
surfaces
in the mouth with the dentifrice compositions according to the present
invention.
Examples & Method of Manufacturing
The following examples further describe and demonstrate embodiments within
the scope of the present invention. These examples are given solely for the
purpose of
illustration and are not to be construed as limitations of the present
invention as many
variations thereof are possible without departing from the spirit and scope.
EXAMPLE I
First Dentifrice Composition Second Dentifrice Composition
Ineredient Wt. % In redient Wt.
Sodium Fluoride 0.24 Color 0.30
Water 12.00 Water 50.00
Flavor 1.00 Flavor 1.00
Sorbitol (c) 58.36 Glycerin 40.26
Titanium Dioxide 0.50 CarbopolTM 2.80
Xanthan Gum 0.50 Sodium Hydroxide(b) l
.00
Sodium Alkyl Sulfate(a)4.00 Sodium Saccharin 0.40
Silica 20.00 Sodium Alkyl Sulfate(a)3.00
Polyethylene Glycol3.00 Sodium Fluoride 0.24
Sodium Saccharin 0.40 Polyoxyethylene I.00
(a) 27.9% solution
(b) 50% solution
(c) 70% solution
The first dentifrice composition is prepared as follows. Start by mixing the
sodium fluoride and saccharin in water. Disperse the xanthan gum in the
sorbitol before
adding to the mixture. Add the polyethylene glycol. Add the flavor system,
titanium
dioxide. and sodium alkyl sulfate. Add the silica. Continue mixing until
homogeneous.
Mill and/or deareate the final product if desired for aesthetic preference.
For the second dentifrice composition, add the water, saccharin, color, and
fluoride to the mixing vessel. Heat to at least 40°C. Premix the
Carbopol and
polyoxyethylene in the glycerin. Add this premix to the mixing vessel and mix
well.
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Premix the flavor and sodium alkyl sulfate until uniform in color. Add this
premix to the
mixing vessel and mix well. Add the sodium hydroxide to the mixture and
continue to
mix until homogeneous.
EXAMPLE II
First DentifriceositionSecond Dentifrice Com position
Comp
In redient Wt. Ineredient Wt.
%
Carboxymethylcellulose0.90 Color 0.30
Water 15.00 Water 29.06
Flavor 1.00 Flavor 1.00
Glycerin 24.76 Triclosan 0.60
Calcium Peroxide1.00 Carbopol 2.50
Sodium Fluoride 0.24 Sodium Hydroxide(b) 1.00
Sodium Alkyl 4.00 Sodium Saccharin 0.40
Sulfate(a)
Silica 22.00 Sodium Alkyl Sulfate(a~ 2.00
Sodium Carbonate2.00 Betaine 2.90
Sodium Saccharin0.40 Sorbitol (c) 60.00
Sodium Bicarbonate14.50 Sodium Fluoride 0.24
Titanium Dioxide1.00
Xanthan Gum 0.20
Polyethylene 3.00
Glycol
Tetrasodium Pyrophosphate10.00
(a) 27.g% solution
fib) 50% solution
~c~ 70% solution
The first dentifrice composition is prepared as follows. Place the water in a
mixing vessel and add sodium fluoride and saccharin. Disperse the thickening
agents,
carboxymethyleellulose and xanthan gum, in the glycerin, before adding to the
mixture.
Add the polyethylene glycol. Next add the flavor system, titanium dioxide, and
sodium
alkyl sulfate. Add the sodium carbonate. Add the silica and then the sodium
bicarbonate. Lastly, slowly add the tetrasodium pyrophosphate and finally the
calcium
peroxide. Continue mixing until homogeneous. Mill and/or deareate the final
product if
desired for aesthetic preference.
For the second dentifrice composition, add the water, saccharin, color, and
fluoride to the mixing vessel. Heat to at least 40°C. Premix the
Carbopol in the sorbitol.
CA 02231294 1998-03-06
Add this premix to the mixing vessel and mix well. Premix the flavor,
triclosan. and
sodium alkyl sulfate until uniform in color and then add the betaine. Add this
premix to
the mixing vessel and mix well. Add the sodium hydroxide to the mixture and
continue
to mix until homogeneous.
EXAMPLE III
First DentifriceositionSecond Dentifrice Comp osition
Comp
Ingredient Wt. Ingredient Wt.
%
Carboxymethylcellulose0.80 Color 0.30
Water 10.00 Water 48.00
Flavor 1.00 Flavor 0.80
Glycerin 8.00 Glycerin 39.76
Sodium Fluoride 0.24 Carbopol 2.60
Sorbitol (c) 25.06 Sodium Hydroxide(b) 1.00
Sodium Alkyl 4.00 Sodium Saccharin 0.40
Sulfate(a)
Silica 15.00 Sodium Alkyl Sulfate(a) 2.00
Sodium Carbonate2.00 Betaine 2.90
Sodium Saccharin0.40 Polyoxyethylene 2.00
Sodium Bicarbonate30.00 Sodium Fluoride 0.24
Titanium Dioxide0.X0
Polyethylene 3.00
Glycol
(a) 27.9% solution
(b) 50% solution
W 70% solution
The first dentifrice composition is prepared as follows. Add the water, sodium
fluoride, and saccharin to a mixing vessel. Disperse the thickening agents,
carboxymethylcellulose, in the glycerin and sorbitol, before adding to the
mixture. Add
the polyethylene glycol, flavor system, and titanium dioxide. Add the sodium
alkyl
sulfate. Next add the sodium carbonate, silica, and then the sodium
bicarbonate.
Continue mixing until homogeneous. Mill and/or deareate the final product if
desired for
aesthetic preference.
For the second dentifrice composition, add the water, saccharin, color, and
fluoride to the mixing vessel. Heat to at least 40°C. Premix the
Carbopol and
polyoxyethylene in the glycerin. Add this premix to the mixing vessel and mix
well.
Premix the flavor and sodium alkyl sulfate until uniform in color and then add
the
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betaine. Add this premix to the mixing vessel and mix well. Add the sodium
hydroxide
to the mixture and continue to mix until homogeneous.
EXAMPLE IV
First DentifriceositionSecond Dentifrice Com position
Comp
Ineredient Wt. Ingredient Wt.
%
Carboxymethylcellulose0.45 Color 0.30
Water 5.00 Water 48.00
Flavor 0.90 Flavor 0.80
Glycerin 34.00 Glycerin 38.44
Xanthan Gum 0.25 Carbopol 2.60
PoloxamerTM 3.00 Sodium Hydroxide~b) 1.00
Sodium Alkyl 4.00 Sodium Saccharin 0.40
Sulfate~a)
Silica 19.00 Sodium Alkyl Sulfate~a) 2.00
Sodium Carbonate2.00 Betaine 2.90
Sodium Saccharin0.40 Polyoxyethylene 3.00
Sodium Bicarbonate9.00 Sodium Fluoride 0.56
Titanium Dioxide1.00
Polyethylene 3.00
Glycol
Glass H Polyphosphate10.00
Propylene Glycol8.00
Via) 27.9% solution
fib) 50% solution
The first dentifrice composition is prepared as follows. Add the saccharin and
water to a mixing vessel. Disperse the thickening agents, carboxymethyl
cellulose and
xanthan gum, in the glycerin. Add this mixture of dispersed thickening agents
in
glycerin to the mixing vessel and mix well. Add the flavor, Poloxamer,
polyethylene
glycol, propylene glycbl, titanium dioxide, and sodium alkyl sulfate to the
mixture and
mix until homogeneous. Next add the sodium carbonate and the silica. After
mixing,
add the sodium bicarbonate. Finally add the polyphosphate. Continue stirring
the
mixture until homogeneous.
For the second dentifrice composition, add the water, saccharin, color, and
fluoride to the mixing vessel. Heat to at least 40°C. Premix the
Carbopol and
polyoxyethylene in the glycerin. Add this premix to the mixing vessel and mix
well.
Premix the flavor and sodium alkyl sulfate until uniform in color and then add
the
CA 02231294 2001-02-19
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betaine. Add this premix to the mixing vessel and mix well. Add the sodium
hydroxide
to the mixture and continue to mix until homogeneous.
EXAMPLE V
In redient Wei h
Glycerin 40.00
Water 49.76
Betaine 2.90
Sodium Fluoride 0.24
Sodium Saccharin 0.40
Sodium Alkyl Sulfate 2.00
(a)
Flavor System 0.80
Color 0.30
Carbopol 2.60
Sodium Hydroxide(b) 1.00
Via) 27.9% solution
(b) 50% solution
The dentifrice composition is prepared as follows. Add the water, saccharin,
color. and fluoride to the mixing vessel. Heat to at least 40°C. Premix
the Carbopol in
the glycerin. Add this premix to the mixing vessel and mix well. Premix the
flavor and
sodium alkyl sulfate until uniform in color and then add the betaine. Add this
premix to
the mixing vessel and mix well. Add the sodium hydroxide to the mixture and
continue
to mix until homogeneous.
EXAMPLE VI
In~ redient Weight
Glycerin 32.26
Water 38.00
Sodium Fluoride 0.24
Sodium Saccharin 0.40
Silica 20.00
Sodium Alkyl Sulfate 4.00
(a)
Flavor System 0.80
Color 0.30
JR-30M PolyQuat M 4.00
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~a~ 27.9% solution
Examples VI is prepared as follows. Add the water, saccharin. color. and
fluoride
to the mixing vessel. Heat to at least 40°C. Premix the PolyQuat in the
glycerin. Add
this premix to the mixing vessel and mix well. Premix the flavor and sodium
alkyl
sulfate until uniform in color and add this premix to the mixing vessel. Add
the silica to
the mixture and continue to mix until homogeneous. Mill and/or deareate the
final
product if desired for aesthetic preference.